Those skilled in the art of interventional medicine are familiar with various types of deflectable shaft catheters used to deliver medical therapy and/or provide medical monitoring. In many cases, a shaft of such a catheter has a pull wire extending along a length thereof, wherein a distal end of the pull wire is anchored to the shaft at a location just distal to a deflectable segment of the shaft. A proximal end of the pull wire is typically secured to a control member subassembly of the catheter, for example, being mounted in a handle of the catheter and including an operator interface. Thus, an operator, when grasping the catheter handle, can actuate the pull wire by applying a force to the operator interface, thereby deflecting the catheter shaft to maneuver a distal portion of the shaft toward a target site within a body of a patient. Although a variety of assemblies suitable for deflectable shaft catheters are known in the art, there is still a need for new assemblies that can enhance operator functionality while having a relatively simple construction.